SCIENCE AND SUPERSTITION. 193 



movement of tables might be found in the unconscious 1855. 

 action of the muscles of those present, and devised an 

 instrument which he believed adequate to detect it, and 

 to bring to the involuntary operators the conviction that 

 the phenomena, imagined spiritual, had been caused by 

 themselves. I remember hearing him at an evening 

 party at Sir John HerschePs explain the action of this 

 instrument, the indicator. A number of ladies and gentle- 

 men listened with interest and attention ; the explanation 

 seemed satisfactory, and was received with the respect 

 due to the great fame of its author. Mr. De Morgan, who 

 was known to be one of those whose credulity required 

 a check, stood by with some amusement on his face. I 

 almost wished him to tell some of those things which 

 he had seen which made him doubt the sufficiency of 

 the explanation. But he said it would be useless. 



This occurred before the lecture was printed, but it 

 had, I think, been delivered. 



